In a statement released Friday night, Christopher Nolan expressed his sadness about the shooting at a movie theater in Aurora, Colo. A gunman opened fire on an audience watching a midnight screening of the highly anticipated movie, killing 12 and injuring 59.

Nolan called movies a great American art form and said watching one is an important and joyful pastime. He called the theater his home, and said the fact that someone would commit an act of violence against innocent people there is savage and "devastating."

He added that the cast and crew's thoughts are with the victims and their families.

Twelve people are dead and 59 more are injured after a mass shooting at a movie theater near Denver. Aurora (Colo.) Police Chief Dan Oates said 10 people died at the theater, and two others died at an area hospital.

The shooting happened during a midnight showing of the new Batman movie The Dark Knight Rises.

Oates said the shooting happened at around 12:30 a.m, about 15 minutes after the movie started, at the Century 16 Movie Theater at the Town Center at Aurora mall. Aurora is just to the southeast of Denver.

KUSA reports one person is in custody. Witnesses said the gunman was wearing all black, a bulletproof vest and what one witness described as a "riot helmet" during the attack.

One eyewitness told KUSA that the suspect threw two gas canisters into the auditorium after kicking in the door. The witness said no one reacted at first, thinking it may have been a stunt for the movie premiere.

"He looked so calm when he did it," the eyewitness said. "It was like scary. He waited for both the bombs to explode before he did anything. Then, after both of them exploded, he began to shoot."

The witnesses said he - at first - fired into the air and then started shooting towards the people.

"He had no specific target. He just started letting loose," the eyewitness said.

"He appeared at the front of the theater and released a gas canister," Oates said. Movie theater management came on loudspeakers and told everyone to evacuate the theater.

NBC's Pete Williams says the suspect has been identified by federal officials as James Holmes, 24. They said he may have been driving a white Kia with Tennessee license plates.

Police spokesperson Jacque Montgomery said Holmes was a student at the University of Colorado School of Medicine in Denver until last month. Montgomery said she did not know when he started school or why he withdrew.

Oates said 10 people were killed inside the theater. Four others died at area hospitals. Most of those affected were in Theater 9, but patrons in adjoining theaters were injured as well by bullets that passed through walls.

"This is a horrific scene, and our hearts go out to the families," Oates said.

The youngest confirmed victim was 3 months old, KUSA reports. Additional victims were treated for chemical exposure. Those who were not injured were taken to nearby Gateway High School.

Some of the victims were taken to Swedish Medical Center, which was alerted to a mass casualty incident and told to prepare for 20 people, KUSA reports. More victims were taken to Aurora Medical Center, Children's Hospital and the University of Colorado Hospital, where the 3-month-old baby was taken. The 3-month old was reported as treated and released.

Earlier reports indicated 14 people had been killed, but KUSA later confirmed that 12 people were dead, according to police. They also revised the injury numbers down to 38.

NBC News said they have confirmed from Defense Department officials that two Air Force Reservists and two Navy servicemembers were injured in the shooting. None of the three were reported killed, they said.

Police spokesman Frank Fania told CNN a suspect was arrested in a rear parking lot of the theater.

"He did not resist. He did not put up a fight," Fania said.

Williams said one of the most peculiar things was that when the suspect was arrested, he waited calmly in the parking lot; He didn't try to resist, he didn't try to turn his weapons on himself.

The shooter used at least four guns -- an "AK type" rifle, a shotgun and two handguns, a federal law enforcement official told CNN.

When he was arrested, he alluded to having more explosives at his North Aurora home, according to Dave Joly, head of the FBI in Denver. Authorities are checking the home as well as all the cars in the theater's parking lot, KUSA said.

Police reported that the suspect's home was believed to be booby-trapped. Residents in the Aurora apartment complex have been evacuated. Officers from at least three police agencies and the FBI are working on the scene.

Officials said there is no evidence of a second suspect in the shooting.

President Barack Obama issued a statement saying he and first lady Michelle Obama were "shocked and saddened" by the shooting and pledged the administration's support for victims of the shooting.

Michelle and I are shocked and saddened by the horrific and tragic shooting in Colorado. Federal and local law enforcement are still responding, and my Administration will do everything we can to support the people of Aurora in this extraordinarily difficult time. We are committed to bringing whoever was responsible to justice, ensuring the safety of our people and caring for those who have been wounded. As we do when confronted by moments of darkness and challenge, we must now come together as one American family. All of us must have the people of Aurora in our thoughts and prayer as they confront the loss of family, friends and neighbors, and we must stand together with them in the challenging hours and days to come.

The president had been expected to make remarks regarding the shooting while at a stop in southwest Florida on Friday, but it was later reported that he had cancelled his Florida stop and was returning to Washington.

Mitt Romney released a statement about the shooting as well, saying he and wife Ann "are praying for the families and loved ones of the victims during this time of deep shock and immense grief. We expect that the person responsible for this terrible crime will be quickly brought to justice."

Aurora, a Denver suburb, is about 13 miles from Littleton, Colo. -- site of the April 1999 Columbine High School massacre. In that incident, two teenage students armed themselves with guns and bombs and opened fire inside the high school, killing 13 people and wounding 23 others before taking their own lives.

Warner Brothers, producers of The Dark Knight Rises said Friday that they were canceling plans for a red carpet premiere for the film in Paris that had been scheduled for Friday evening.

A news conference promoting the film with director Christopher Nolan and cast members Christian Bale, Anne Hathaway and Morgan Freeman at Paris' hotel Le Bristol was canceled.

Suspect Holmes will make his first court appearance at 8:30 a.m. Mountain Time on Monday.